单项选择题

Research discovered that plants infected with a virus give off a gas that______disease resistance in neighboring plants.

A．contracts
B．activates
C．maintains
D．prescribes
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单项选择题
Perhaps there is some element associated with the preservation of memory that, when carried to ______, inhibits that memory instead.
A．extreme
B．excessive
C．excess
D．exceed
单项选择题
Where will the man be while the technician looks at the camera
A．In the library.
B．In the company.
C．In the kiosk.
D．In the bar.
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